diff options
| author | Stefan Nilsson XK <stefan.xk.nilsson@stericsson.com> | 2011-05-11 19:48:05 +0400 |
|---|---|---|
| committer | Chris Ball <cjb@laptop.org> | 2011-05-25 07:53:50 +0400 |
| commit | 06e8935febe687e2a561707d4c7ca4245d261dbe (patch) | |
| tree | 0eef896f5b1614576fb0a1b744b4f87e8124f515 | |
| parent | 253d6a280f77a9b61a76f9b1bfb83545fbd58726 (diff) | |
| download | linux-06e8935febe687e2a561707d4c7ca4245d261dbe.tar.xz | |
mmc: sdio: optimized SDIO IRQ handling for single irq
If there is only 1 function interrupt registered it is possible to
improve performance by directly calling the irq handler and avoiding
the overhead of reading the CCCR registers.
Signed-off-by: Per Forlin <per.forlin@linaro.org>
Acked-by: Ulf Hansson <ulf.hansson@stericsson.com>
Reviewed-by: Nicolas Pitre <nicolas.pitre@linaro.org>
Signed-off-by: Chris Ball <cjb@laptop.org>
| -rw-r--r-- | drivers/mmc/core/sdio_irq.c | 33 | ||||
| -rw-r--r-- | include/linux/mmc/card.h | 1 |
2 files changed, 33 insertions, 1 deletions
diff --git a/drivers/mmc/core/sdio_irq.c b/drivers/mmc/core/sdio_irq.c index b3001617e67d..03ead028d2ce 100644 --- a/drivers/mmc/core/sdio_irq.c +++ b/drivers/mmc/core/sdio_irq.c @@ -31,6 +31,17 @@ static int process_sdio_pending_irqs(struct mmc_card *card) { int i, ret, count; unsigned char pending; + struct sdio_func *func; + + /* + * Optimization, if there is only 1 function interrupt registered + * call irq handler directly + */ + func = card->sdio_single_irq; + if (func) { + func->irq_handler(func); + return 1; + } ret = mmc_io_rw_direct(card, 0, 0, SDIO_CCCR_INTx, 0, &pending); if (ret) { @@ -42,7 +53,7 @@ static int process_sdio_pending_irqs(struct mmc_card *card) count = 0; for (i = 1; i <= 7; i++) { if (pending & (1 << i)) { - struct sdio_func *func = card->sdio_func[i - 1]; + func = card->sdio_func[i - 1]; if (!func) { printk(KERN_WARNING "%s: pending IRQ for " "non-existent function\n", @@ -186,6 +197,24 @@ static int sdio_card_irq_put(struct mmc_card *card) return 0; } +/* If there is only 1 function registered set sdio_single_irq */ +static void sdio_single_irq_set(struct mmc_card *card) +{ + struct sdio_func *func; + int i; + + card->sdio_single_irq = NULL; + if ((card->host->caps & MMC_CAP_SDIO_IRQ) && + card->host->sdio_irqs == 1) + for (i = 0; i < card->sdio_funcs; i++) { + func = card->sdio_func[i]; + if (func && func->irq_handler) { + card->sdio_single_irq = func; + break; + } + } +} + /** * sdio_claim_irq - claim the IRQ for a SDIO function * @func: SDIO function @@ -227,6 +256,7 @@ int sdio_claim_irq(struct sdio_func *func, sdio_irq_handler_t *handler) ret = sdio_card_irq_get(func->card); if (ret) func->irq_handler = NULL; + sdio_single_irq_set(func->card); return ret; } @@ -251,6 +281,7 @@ int sdio_release_irq(struct sdio_func *func) if (func->irq_handler) { func->irq_handler = NULL; sdio_card_irq_put(func->card); + sdio_single_irq_set(func->card); } ret = mmc_io_rw_direct(func->card, 0, 0, SDIO_CCCR_IENx, 0, ®); diff --git a/include/linux/mmc/card.h b/include/linux/mmc/card.h index d8dffc992ce2..4910dec47bb7 100644 --- a/include/linux/mmc/card.h +++ b/include/linux/mmc/card.h @@ -191,6 +191,7 @@ struct mmc_card { struct sdio_cccr cccr; /* common card info */ struct sdio_cis cis; /* common tuple info */ struct sdio_func *sdio_func[SDIO_MAX_FUNCS]; /* SDIO functions (devices) */ + struct sdio_func *sdio_single_irq; /* SDIO function when only one IRQ active */ unsigned num_info; /* number of info strings */ const char **info; /* info strings */ struct sdio_func_tuple *tuples; /* unknown common tuples */ |